<!DOCTYPE html>
<html lang="zh-CN">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <h2></h2>
    <button onclick="saveDate()">点我保存一个数据</button>
    <button onclick="readData()">点我读取一个数据</button>
    <button onclick="deleteData()">点我删除一个数据</button>
    <button onclick="deleteAllData()">点我清空一个数据</button>
    <script type="text/javascript">
        let p = { name: "张三", age: 18 }

        function saveDate() {
            sessionStorage.setItem('msg', "hello!!!");
            sessionStorage.setItem('msg2', 666)
            sessionStorage.setItem('person', JSON.stringify(p))
        }

        function readData() {
            console.log(sessionStorage.getItem('msg'));
            console.log(sessionStorage.getItem('msg2'));

            const result = sessionStorage.getItem('person')
            console.log(JSON.parse(result));

            console.log(sessionStorage.getItem('msg3'));
        }

        function deleteData() {
            sessionStorage.removeItem('msg2')
        }

        function deleteAllData() {
            sessionStorage.clear()
        }
    </script>
</body>

</html>